• Journal of the Korean Society for Nondestructive Testing
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• v.26 no.2
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• pp.108-114
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• 2006

Transient and asymmetric density distributions of butane flow have been investigated from laser image signals by developed three-dimensional digital speckle tomography. Moved signals of speckles have been captured by multiple CCD images in three angles of view simultaneously because the flows were asymmetric and transient. The signals of speckle movements between no flow and downward butane flow from a circular half opening have been calculated by a cross-correlation tracking method so that those distances can be transferred to deflection angles of laser rays fur density gradients. The three-dimensional density fields have been reconstructed from the fringe shift signal which is integrated from the deflection angle by a real-time multiplicative algebraic reconstruction technique (MART).

• Journal of Broadcast Engineering
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• v.21 no.2
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• pp.252-260
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• 2016

The performance of human detection system is affected by camera location and view angle. In 2D image acquired from such camera settings, humans are displayed in different sizes. Detecting all the humans with diverse sizes poses a difficulty in realizing a real-time system. However, if the size of a human in an image can be predicted, the processing time of human detection would be greatly reduced. In this paper, we propose a method that estimates human size by constructing an indoor scene in 3D space. Since the human has constant size everywhere in 3D space, it is possible to estimate accurate human size in 2D image by projecting 3D human into the image space. Experimental results validate that a human size can be predicted from the proposed method and that machine-learning based detection methods can yield the reduction of the processing time.

• Journal of Radiation Protection and Research
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• v.43 no.2
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• pp.75-84
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• 2018

Background: Gamma-ray spectrometry helps in radiation shielding problems and different applications of radioisotopes. Experimental arrangements including broad beam geometries are widely used. The aim is to investigate and evaluate the ${\gamma}-ray$ spectra via attenuation by environmental materials. Materials and Methods: The photo peak to nominated parts in the ${\gamma}-ray$ spectra and the attenuation coefficients ${\mu}_b/{\rho}$ from broad beam geometries are measured for the materials water, soil, sand and cement at the energies 0.662, 1.25, and 1.332 MeV with a $3{^{\prime}^{\prime}}{\times}3{^{\prime}^{\prime}}$ NaI(Tl) detector. Results and Discussion: The ${\gamma}-ray$ spectra vary according to changes in the effective atomic number $Z_{eff}$ of the attenuator, the photon energy and the solid angle. The peak to total ratios are the most sensitive parts to variations in the experimental conditions and overturn in the region 0.663 MeV to 1.332 MeV. This is indicated as inversion trend. The results are discussed in view of $Z_{eff}$ and the experimental conditions. The intensity build-up is larger at the lower energy and larger scattering angles in agreement with Klein-Nishina formula and other results. The build-up factor B is$${\sim_=}$$1 at high ${\gamma}-energies$ and small scattering angles. Conclusion: The sensitivity to material characteristics decrease gradually from peak: to total, to Compton valley, to Compton plateau ratios. Rigorous collimation is necessary at small energies. Cement, of the largest $Z_{eff}$, is characterized by the maximum broad beam mass attenuation coefficients ${\mu}_b/{\rho}$. The obtained results provide information to decide for the suitable experimental set-up based on aim of the work.

• Spatial Information Research
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• v.12 no.4 s.31
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• pp.351-370
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• 2004

At present, environmental monitoring of linear infrastructure is based mainly on field sampling. The 'integrated mapping' approach has received only limited attention from field scientists. The increased environmental regulation of corridor targets has required remote sensing research to develop a sensor or technique for targets ranging from 15 m to 100 m in swath width. In an attempt to identify the optimal remote sensing system for linear targets, an overview is provided of the application requirements and the technology currently available. The relative limitation of traditional remote sensing systems in such a linear application is briefly discussed. It is noted that airborne video could provide, in a cost-effective manner, information required for a very narrow and long strip target utilising the narrow view angle and dynamic stereo coverage. The value of this paper is warranted in proposing a new concept of video infrastructure monitoring as a future research direction in the recognition of sensor characteristics and limitations.

• Journal of the Korea Society of Computer and Information
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• v.25 no.5
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• pp.117-126
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• 2020

In this study, a 3D simulation program was used to produce a bodice prototype of a middle-aged male in their 40s and 50s and then analyze the appearance evaluation and airgap, sectional view, color distribution through virtual wearing to compare and analyze the differences between patterns. Through this, it was intended to provide basic data necessary for pattern development to companies that manufacture and produce clothing for middle-aged men. As a result of analyzing, J pattern was analyzed as the most suitable body shape pattern for middle-aged men. E pattern was too tight and L pattern and N pattern had too much spaces. However, J patternt was analyzed that correction was necessary in setting center back and center front length. The aging phenomenon in which the back is slightly bent forward and shoulders are also inclined is expected to appear, so it is necessary to adjust the front-to-back length, shoulder angle, and shoulder length. It is considered that after developing the research pattern by modifying J pattern, it is necessary to develop a body shape prototype for middle-aged men through actual clothing experiments on middle-aged men.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1195-1200
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• 2008

This study have goal with conceptual design for Offshore Structures of high pressure control valve for localization. Ball valve for development accomplished with flow analysis based on provision of ANSI B16.34, ANSI B16.10, ANSI B16.25 In order to localize the Offshore Structures high pressure control valve. Numerical simulation using CFD(Computational Fluid Dynamic) in order to predict a mass flow rate and a flow coefficient form flow dynamic point of view. The working fluid assumed the glycerin($C_3H_8O_3$). The valve inlet and outlet setup a pressure boundary condition. The outlet pressure was fixed by atmospheric pressure and calculated until increasing 1bar to 10bar. CFD analysis used STAR-CCM+ which is commercial code and Governing equations were calculated by moving mesh which is rotated 90 degrees when ball valve operated opening and closing in 1 degree interval. The result shows change of mass flow rate according to opening and closing angle of valve. Flow decrease observed open valve that equal percentage flow paten which is general inclination of ball valve. Relation with flow and flow coefficient can not be proportional according to inlet pressure when compare with mass flow rate. Because flow coefficient have influence in flow and pressure difference. Namely, flow can be change even if it has same Cv value. The structural analysis used ANSYS which is a commercial code. Stress analysis result of internal pressure in valve showed lower than yield strength. This is expect to need more detail design and verification for stem and seat structure.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.11 no.4
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• pp.331-338
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• 2017

In this study, a portable x-ray generator was manufactured and a real-time image acquisition system was constructed using the image intensifier from the generated generator. We have developed a real - time position error verification system that can verify whether the artificial joint position is different from the initial image from the acquired image. The template image of the region of interest is extracted from the reference image using the pattern matching technique and compared with the image to be compared. As a result, It is shown that real - time position error verification is achieved by displaying the difference angle. This system is portable type, has a self-shielding facility, and the output of the irradiation device can be manufactured in a small size of 1kw and can be used as a portable type. In case of emergency patients in the non-destructive field for industrial use, It has proved effective for use in small areas such as feet.

• The Journal of Korean Medical History
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• v.21 no.2
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• pp.13-28
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• 2008

Medical Science in general is a study dedicated to human. It is important to understand how human is being seen in medical science. The difference of this perspective among various medical science in different parts of the world shows the difference in ways of understanding human, and furthermore, difference in ways of understanding diseases. On the other side, Oriental Medicines tends to perceive human as a whole. Heo Joon's perspective on human is elaborated in his book, Dongeuibogam. The foundation of this perspective is found is the Thesis of Four Generals and Five Constants, Neijing. There are many discussions in the Thesis of Four Generals and Five Constants, which include the thesis of correspondence between nature and human: which define the relationship between human and nature in terms of four generals and five constants, and the thesis of xing and color: which offers the tool of making diagnosis on Four Generals and Five Constants, since xing and color designates the result of Four Generals and Five Constants. Other methods are also merely ways of expressing Four Generals and Five Constants in different angle. After all, the perspective of human shown by Heo Joon can be explained in one word as the thesis of Four Generals and Five Constants, and the principles of its theory, which are the thesis of correspondence between nature and human and the thesis of xing and color are also nothing more than a tool of underatanding Four Generals and Five Constants more efficiently.

• Korean Journal of Applied Biomechanics
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• v.16 no.2
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• pp.165-174
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• 2006

The purpose of this study was to review the relevant literature about coaching and thereupon, survey the coaching methods used for golfer lesson to reinterpret them and thereby, describe in view of kinetics the swing errors committed frequently by amateur golfers and suggest more scientific golfer coaching methods. For this purpose, kinetic elements were divided into precision and power ones and therewith, the variables affecting such elements were identified. On the other hand, swings were divided into address, take-back, back-swing, back-swing top, down-swing, impact and follow-through to determine 20 variables for each form and thereby, define their errors to determine the relations between their frequency and errors. For this study, a total of 60 amateur golfer were sampled, and their swing forms were photographed with two high-speed digital cameras, and the resultant images were analyzed to determine the errors of each form kinetically, which would be analyzed again with the program V1-5000. The results of this study can be summarized as follows; The kinetic elements could be identified as precision, power and precise power. Thus, setup and trajectory were classified into precision elements, while differences of inter-joint angles, cocking and delayed hitting. Lastly, timing and axial movement were classified into precise power elements. Three errors were identified in association with setup. The errors related with trajectory elements accounted for most (7) of the 20 errors. Three errors were determined for inter-joint angle differences, and one error was associated with cocking and delayed hitting. Lastly, one error was classified into timing error, while five errors were associated with axial movement. Finally, as a result of arranging the errors into a cross table, it was found that the errors were associated with each other between take-back and back-swing, take-back and follow-through, back-swing and back-swing top, and between back-swing and down-swing. Namely, an error would lead to other error repeatedly. So, it is more effective to identify all the errors for every form and correct them comprehensively rather than single out the errors and correct them one by one.

• Journal of the Korean institute of surface engineering
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• v.40 no.5
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• pp.241-244
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• 2007

$MgF_2$/Cr/$MgF_2$, $MgF_2$/Cu/$MgF_2$ and $MgF_2$/Al/$MgF_2$ multi-layered thin films were fabricated by evaporation system. $MgF_2$ and Cr(Cu, And Al) was selected as a low refractive index material and mid reflector layer, respectively. Optical properties including color effect were systematically studied in terms of different film layer by using spectrophotometer. Experimental results were compared to the simulation result. The films consistings of $MgF_2$/Cr/$MgF_2$, $MgF_2$/Cu/$MgF_2$, $MgF_2$/Al/$MgF_2$ multi-layered thin films showed wavelength range of $430{\sim}780nm$, typically color range between greenish yellow and orange at view angle of $45^{\circ}$. It was confirmed that this experimental result was well matched with simulation result.